Journal: Brain Stimulation 11(1): 158-165 (2018)
Authors: L Carmi, U Alyagon, N Barnea-Ygael, J Zohar, R Dar, A Zangen
Obsessive Compulsive Disorder (OCD) is a chronic and disabling disorder with poor response to pharmacological treatments. Converging evidences suggest that OCD patients suffer from dysfunction of the cortico-striato-thalamo-cortical (CSTC) circuit, including in the medial prefrontal cortex (mPFC) and the anterior cingulate cortex (ACC).
The authors set out to examine whether modulation of mPFC-ACC activity by Deep TMS™ affects OCD symptoms.
Forty-one treatment resistant OCD patients were treated with either high frequency (HF; 20 Hz) or sham deep TMS of the mPFC and ACC for five weeks in a double-blinded manner. Both treatments were administered following symptoms provocation. EEG measurements during a Stroop task were acquired o examine changes in error-related activity. Clinical response to treatment was determined using the Yale-Brown-Obsessive-Compulsive-Scale (YBOCS).
Following completion of the study, the response rate in the HF group (n=18) was significantly higher than that of the sham group (n=15) for at least one month following the end of the treatment. Notably, the clinical response in the HF group correlated with increased Error Related Negativity (ERN) in the Stroop task, an electrophysiological component that is attributed to ACC activity.
This study indicates that HF Deep TMS over the mPFC-ACC, when applied following provocation of OCD symptoms, is safe, tolerable and effective in reducing OCD symptoms.